Nucleic acids bacterial

These agents profoundly prevent production of bacterial nucleic acids and inhibit genetic replication. 

Another logical means of confronting the diseases of bacterial infection is to prevent the bacteria from reproducing. This may be readily achieved by targeting the bacterial nucleic acids. 

They contain a selection marker for the easy separation and purification of the vector from bacterial nucleic acids. 

Several antibacterial drugs inhibit bacterial nucleic acid synthesis by inhibiting the production of folic acid.17 Folic acid serves as an enzymatic cofactor in a number of reactions, including synthesis of bacterial nucleic acids and certain essential amino acids. The pathway for synthesis of these folic acid cofactors is illustrated in Figure 33-2. Certain antibacterial drugs block specific steps in the folate pathway, thus impairing the production of this enzymatic cofactor and ultimately impairing the production of nucleic acids and... 

The sulfonamides include sulfadiazine, sulfamethizole, and similar agents (see Table 33-4). Sulfonamides interfere with bacterial nucleic acid production by disrupting folic acid synthesis in susceptible bacteria. Sulfonamide drugs are structurally similar to PABA, which is the substance used in the first step of folic acid synthesis in certain types of bacteria (see Fig. 33-2). Sulfonamides either directly inhibit the enzyme responsible for PABA utilization or become a substitute for PABA, which results in the abnormal synthesis of folic acid. In either case, folic acid synthesis is reduced, and bacterial nucleic acid synthesis is impaired. 

Trimethoprim (Proloprim, Trimpex) interferes with the bacterial folic acid pathway by inhibiting the dihydrofolate reductase enzyme in susceptible bacteria (see Fig. 33-2). This enzyme converts dihydrofolic acid to tetrahydrofolic acid during the biosynthesis of folic acid cofactors. By inhibiting this enzyme, trimethoprim directly interferes with the production of folic acid cofactors, and subsequent production of vital bacterial nucleic acids is impaired. 

Figure 13.15 Comparison of A14C versus <513C for bacterial nucleic acids and potential sources for the (a) entire York River estuary, (b) the freshwater, (c) mid-salinity, and (d) high-salinity (river mouth) regions in the estuary. Boxes are the 95% confidence intervals for the potential end-members in the York. Dotted lines represent the solution space from one run of a model. (Modified from McCallister et ah, 2004.)...

Jones25 described the isolation of bacterial nucleic acids from Mycobacterium tuberculosis, My. phlei, and Sarcina lutea by precipitation with the... 

Bacterial nucleic acids were hydrolyzed using bovine pancreatic ribonuclease and deoxyribonuclease.37 Deoxyribonuclease treatment of disrupted bacterial suspensions has also been reported.38... 

Although bacterial nucleic acids and nucleoproteins have been recognized since the turn of the centuryonly the last decade has witnessed research on the low-molecular nucleotides and nucleosides in bacterial cells. Simultaneously, a variety of such substances from other materials (such as plants, yeasts, and animal tissues) have been isolated. Most of these substances are present in small amounts in the cell, and the introduction of refined techniques (such as ion-exchange chromatography, paper chromatography, and paper electrophoresis) were required for their isolation. The isotope technique has also contributed substantially to our knowledge of these substances. 

Bacterial infections are treated with antibiotics. There are many antibiotics available, but they fall into three major groups based on their mode of action inhibitors of bacterial nucleic acid synthesis inhibitors of cell wall synthesis and inhibition of bacterial protein synthesis. Resistance of bacteria to commonly-used antibiotics has become a major problem necessitating the development of new antibiotics. Tuberculosis infection is difficult to treat and requires a combination of at least three different antibiotics. 

Observations indicate that the enrichments in the pyrimidines (likely, but of unknown magnitude) and the depletions in the purines (hypothetical, but apparently needed to explain the results) balance at least roughly. Pioneering analyses of the carbon-isotopic compositions of bacterial nucleic acids were reported by Blair et al. (1985), who found nucleic acids enriched in relative to biomass by 0.6%o. More recently, this work has been very nicely extended by Richard Coffin and his coworkers, who report that bacterial nucleic acids are enriched relative to biomass by about 0.3%o (Coffin et al. 

Fluoroquinolones inhibit bacterial topoisomerases II and IV Streptogramins are recently introduced inhibitors of bacterial nucleic acid synthesis Vancomycin inhibits the synthesis of precursors of the linear peptidoglycan chains of the bacterial cell wall... 

Effects on bacterial protein synthesis Effects on bacterial nucleic acid syntheses ... 

Biosensors for bacterial detection involve biological recognition components such as presence of the biomarkers, nucleic acid, antibodies or aptamer attached on a transducer. However, in this chapter, bacterial nucleic acid will be described in detail [13]. 

In the hybridization experiments with the ground nut, an RNA was, in fact, found, which hybridized particularly readily with DNA (Table 2). This RNA was eluted from the MAK column by the NaCl gradient at the same position as the mRNA from the hypocotyls of the soya bean mentioned above. It may be mentioned that in the case of the separation of bacterial nucleic acids, mRNA is also eluted in the same position. Thus, there is scarcely any doubt in the case of the ground nut that the RNA in question is indeed a mRNA. 

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